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Bose-Einstein condensation in a stiff TOP trap with adjustable geometry

E. Hodby·G. Hechenblaikner·O. M. Marago'·J. Arlt·S. Hopkins·C. J. Foot
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Abstract

We report on the realisation of a stiff magnetic trap with independently adjustable trap frequencies, $ω_z$ and $ω_r$, in the axial and radial directions respectively. This has been achieved by applying an axial modulation to a Time-averaged Orbiting Potential (TOP) trap. The frequency ratio of the trap, $ω_z / ω_r$, can be decreased continuously from the original TOP trap value of 2.83 down to 1.6. We have transferred a Bose-Einstein condensate (BEC) into this trap and obtained very good agreement between its observed anisotropic expansion and the hydrodynamic predictions. Our method can be extended to obtain a spherical trapping potential, which has a geometry of particular theoretical interest.

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E. Hodby, G. Hechenblaikner, O. M. Marago', J. Arlt, S. Hopkins, C. J. Foot. 2000-04-03. Bose-Einstein condensation in a stiff TOP trap with adjustable geometry. https://doi.org/10.1088/0953-4075%2F33%2F19%2F319

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